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101.
Mesenchymal stem cells (MSCs) are multipotent cells with a number of potential therapeutic applications. At present, they are being used in a clinical trial for the treatment of myocardial infarction and are being studied as a therapy for other vascular disorders. Treatments of neurologic disorders and anticancer therapy with MSCs have progressed in light of the migratory properties of MSCs to brain injury and tumors. The osteogenic potential of MSCs is being exploited in work investigating their use in bone regeneration therapy, and the immunomodulatory function of MSCs is being evaluated as a possible therapy for graft-versus-host disease. Here, the authors review recent work contributing to the knowledge of MSC biology and the advances in gene therapy and tissue regeneration using MSCs.  相似文献   
102.
Studies suggest elevated serum intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) levels may be markers of pulmonary arterial hypertension in systemic sclerosis (SSc-PAH). We sought to evaluate whether ICAM-1 and VCAM-1 levels are useful screening biomarkers for incident SSc-PAH. In this cross-sectional study, four groups were selected from the Australian Scleroderma Cohort Study: group 1 (n?=?15) had definite PAH; group 2 (n?=?19) had interstitial lung disease (ILD); group 3 (n?=?30) were SSc-controls; and group 4 (n?=?34) were healthy controls. Serum ICAM-1 and VCAM-1 levels were measured using the Millipore Milliplex MAP Human 2-Plex Panel. There were no differences in ICAM-1 levels in the PAH versus ILD group (263.0?±?85.4 vs 380.4?±?168.3 ng/mL, p?=?0.136), SSc-controls (263.0?±?85.4 vs 253.1?±?98.0 ng/mL, p?=?1.00), or healthy controls (263.0?±?85.4 vs 201.8?±?57.2 ng/mL, p?=?0.093). Similarly, there were no differences in VCAM-1 level in PAH versus ILD groups (1476.2?±?434.9 vs 1424.8?±?527.6 ng/mL, p?=?1.00) and SSc-controls (1476.2?±?434.9 vs 1409.5?±?341.1 ng/mL, p?=?1.00). SSc subjects had significantly higher levels of ICAM-1 (297.4?±?134.0 vs 201.8?±?57.2 ng/mL, p?<?0.0001) and VCAM-1 compared to healthy controls (1432.7?±?427.4 vs 1125.6?±?273.4 ng/mL, p?<?0.0001). Neither ICAM-1 nor VCAM-1 is a specific screening biomarker of SSc-PAH. Instead, increased levels of these adhesion molecules in SSc, irrespective of pulmonary complications, suggest that they may play a role in SSc pathogenesis.  相似文献   
103.
The acute coronary syndrome is most often caused by plaque rupture and can result in a variety of clinical conditions. There are two general strategies (early invasive versus conservative) currently employed in the treatment of unstable angina or non-ST elevation myocardial infarction. Pooled data from recent clinical trials have demonstrated that high-risk patients benefit from a routine or early invasive approach while certain low-risk subgroups have similar outcomes with a conservative approach. Most patients in the USA are treated aggressively given advances in technology and the relative ease of interventional therapy. The routine invasive approach, however, remains controversial and has important limitations that are not well identified in trials. Furthermore, data from trials are difficult to interpret given their relevance to contemporary practice in today’s cost conscious, health care environment. The decision to pursue an invasive or conservative approach should be based upon an individual patient’s risk profile, and the level of medical therapy should be based on the underlying pathophysiology. The best strategy incorporates aggressive anti-atherosclerotic therapy with early risk stratification and invasive therapy when appropriate—the so-called hybrid approach. Identifying plaque rupture helps identify patients that would benefit from potent antiplatelet, antithrombotic, and anti-inflammatory therapies, and further insight into the natural history of coronary artery disease coupled with continued advances in diagnostic and interventional approaches will hopefully help guide long-term primary and secondary management.  相似文献   
104.
Cross-sectional latent class regression models, also known as switching regressions or hidden Markov models, cannot identify transitions between classes that may occur over time. This limitation can potentially be overcome when panel data are available. For such data, we develop a sequence of models that combine features of the static cross-sectional latent class (finite mixture) models with those of hidden Markov models. We model the probability of movement between categories in terms of a Markovian structure, which links the current state with a previous state, where state may refer to the category of an individual. This article presents a suite of mixture models of varying degree of complexity and flexibility for use in a panel count data setting, beginning with a baseline model which is a two-component mixture of Poisson distribution in which latent classes are fixed and permanent. Sequentially, we extend this framework (i) to allow the mixing proportions to be smoothly varying continuous functions of time-varying covariates, (ii) to add time dependence to the benchmark model by modeling the class-indicator variable as a first-order Markov chain and (iii) to extend item (i) by making it dynamic and introducing covariate dependence in the transition probabilities. We develop and implement estimation algorithms for these models and provide an empirical illustration using 1995-1999 panel data on the number of doctor visits derived from the German Socio-Economic Panel.  相似文献   
105.
ObjectiveTo ascertain whether cannula displacement during cataract surgery with the use of the Luer lock is a common and recognized complication.MethodsA questionnaire was sent to attending physicians on the Royal College of Ophthalmologists U.K. register inquiring about episodes of cannula displacement and complications.ResultsDespite the use of Luer locks, 60 cases of cannula detachment were reported; 196 respondents experienced this complication, and the most common cause of cannula detachment was stromal hydration (50%). Hydrodissection and viscoelastic were experienced by 18% and 17%, respectively. No severe damage resulted in most cases (76 cases), but some serious complications were reported: retinal damage (9%) and vitreous loss (17%).ConclusionsWe recommend that surgeons test the union carefully themselves and then test the system by squirting outside the eye. Additionally, we recommend that a new cannula be used for each stage of the procedure. The viscoelastic cannula, in particular, should not be used for any other purpose.  相似文献   
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Purpose

Various surgical modalities have been used in the surgical management of oral submucous fibrosis with variable results. This prospective study evaluates the efficacy of nasolabial flap in the reconstruction of fibrotomy defect in surgical treatment of oral submucous fibrosis in terms of functional and esthetic outcomes.

Material and method

In this prospective study, we treated 20 patients of oral submucous fibrosis surgically. The surgical protocol was consisting of bilateral fibrotomy, temporal myotomy, and coronoidotomy or coronoidectomy followed by reconstruction of fibrotomy defect with bilateral extended nasolabial flaps. All patients were prescribed with nutritional supplements and antioxidants. Vigorous mouth opening exercise was made compulsory for every patient. Preoperative and postoperative evaluation was done for interincisal mouth opening, function of mastication, and cosmetic results. Patient’s regular follow-up was done for 2 years.

Results

Postoperatively, we noted excellent increase in the interincisal mouth opening relieving trismus. Patient’s ability to chew solid food was increased significantly. Extraoral scar was minimal and well accepted by all the patients. There was no morbidity of the donor site. There was no injury to the facial nerve in all cases. The only drawback was intraoral hair growth which went on reducing with mucosalization of the graft tissue.

Conclusion

Random pattern nasolabial flap is a very good option for intraoral reconstruction of fibrotomy defect in surgical treatment of oral submucous fibrosis with excellent functional and cosmetic results with minimal complications.
  相似文献   
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